Connector: Database connection resolver

Connector will resolve the name into a full database configuration object
with properties like username, password, address, port, protocol etc.

Connector then helps you to turn this Config object into a PDO connection.

Next to the common Config properties, Connector also allows you to define
custom properties on a a database config instance. These custom properties
can then be used by your app to configure the application behaviour.

Cascading configuration

A configuration may define connection properties directly,
or refer to a server and/or cluster by name.

This enables cascading configuration at 3 levels:

db

server

cluster

Using this feature you can define the server or cluster at the db level,
and configure address, username, password, port and custom properties
at a higher level. This way you can quickly mass-reconfigure all
dbs on a given server or cluster.